Add JsonLibraryVersion and generate JsonStringEnumMemberNameAttriute for >= 9.0, EnumMemberAttribute otherwise

src/NJsonSchema.CodeGeneration.CSharp.Tests/EnumTests.cs

@@ -181,6 +181,27 @@ public async Task When_enum_list_uses_string_enums_then_ItemConverterType_is_set
             CSharpCompiler.AssertCompile(code);
         }
 
+        [Fact]
+        public async Task When_enum_list_uses_string_enums_then_ItemConverterType_is_set_for_STJ_target()
+        {
+            // Arrange
+            var schema = NewtonsoftJsonSchemaGenerator.FromType<MyStringEnumListTest>();
+            var data = schema.ToJson();
+            var generator =
+                new CSharpGenerator(schema, new CSharpGeneratorSettings
+                {
+                    ClassStyle = CSharpClassStyle.Poco, 
+                    JsonLibrary = CSharpJsonLibrary.SystemTextJson
+                });
+
+            // Act
+            var code = generator.GenerateFile();
+
+            // Assert
+            await VerifyHelper.Verify(code);
+            CSharpCompiler.AssertCompile(code);
+        }
+
         [Fact]
         public async Task When_enum_is_nullable_then_StringEnumConverter_is_set()
         {

src/NJsonSchema.CodeGeneration.CSharp.Tests/Snapshots/EnumTests.When_enum_is_string_then_generic_StringEnumConverter_is_used_nullable=False.verified.txt

@@ -20,15 +20,15 @@ namespace MyNamespace
     public enum MyClassSize
     {
 
-        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"small")]
+        [System.Runtime.Serialization.EnumMember(Value = @"small")]
         Small = 0,
 
 
-        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"medium")]
+        [System.Runtime.Serialization.EnumMember(Value = @"medium")]
         Medium = 1,
 
 
-        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"large")]
+        [System.Runtime.Serialization.EnumMember(Value = @"large")]
         Large = 2,
 
 

src/NJsonSchema.CodeGeneration.CSharp.Tests/Snapshots/EnumTests.When_enum_is_string_then_generic_StringEnumConverter_is_used_nullable=True.verified.txt

@@ -20,15 +20,15 @@ namespace MyNamespace
     public enum MyClassSize
     {
 
-        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"small")]
+        [System.Runtime.Serialization.EnumMember(Value = @"small")]
         Small = 0,
 
 
-        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"medium")]
+        [System.Runtime.Serialization.EnumMember(Value = @"medium")]
         Medium = 1,
 
 
-        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"large")]
+        [System.Runtime.Serialization.EnumMember(Value = @"large")]
         Large = 2,
 
 

src/NJsonSchema.CodeGeneration.CSharp.Tests/Snapshots/EnumTests.When_enum_list_uses_string_enums_then_ItemConverterType_is_set_for_STJ_target.verified.txt

@@ -0,0 +1,36 @@
+//----------------------
+// <auto-generated>
+// </auto-generated>
+//----------------------
+
+
+namespace MyNamespace
+{
+    #pragma warning disable // Disable all warnings
+
+    public enum MyStringEnum
+    {
+
+        [System.Runtime.Serialization.EnumMember(Value = @"Foo")]
+        Foo = 0,
+
+
+        [System.Runtime.Serialization.EnumMember(Value = @"Bar")]
+        Bar = 1,
+
+
+    }
+
+    public partial class MyStringEnumListTest
+    {
+
+        [System.Text.Json.Serialization.JsonPropertyName("Enums")]
+        // TODO(system.text.json): Add ItemConverterType with enum converter when supported
+        public System.Collections.Generic.ICollection<MyStringEnum> Enums { get; set; }
+
+        [System.Text.Json.Serialization.JsonPropertyName("NullableEnum")]
+        [System.Text.Json.Serialization.JsonConverter(typeof(System.Text.Json.Serialization.JsonStringEnumConverter<MyStringEnum>))]
+        public MyStringEnum? NullableEnum { get; set; }
+
+    }
+}

src/NJsonSchema.CodeGeneration.CSharp/CSharpGeneratorSettings.cs

@@ -120,6 +120,9 @@ public CSharpGeneratorSettings()
         /// <summary>Gets or sets the CSharp JSON library to use (default: 'NewtonsoftJson', 'SystemTextJson' is experimental/not complete).</summary>
         public CSharpJsonLibrary JsonLibrary { get; set; }
 
+        /// <summary>Gets or sets the CSharp JSON library version to use (applies only to System.Text.Json, default: 8.0).</summary>
+        public decimal JsonLibraryVersion { get; set; } = 8.0m;
+
         /// <summary>Gets or sets the CSharp JSON polymorphic serialization style (default: 'NJsonSchema', 'SystemTextJson' is experimental/not complete).</summary>
         public CSharpJsonPolymorphicSerializationStyle JsonPolymorphicSerializationStyle { get; set; }
 

src/NJsonSchema.CodeGeneration.CSharp/Models/EnumTemplateModel.cs

@@ -55,6 +55,9 @@ public EnumTemplateModel(string typeName, JsonSchema schema, CSharpGeneratorSett
         /// <summary>Gets a value indicating whether to use System.Text.Json</summary>
         public bool UseSystemTextJson => _settings.JsonLibrary == CSharpJsonLibrary.SystemTextJson;
 
+        /// <summary>Gets or sets the CSharp JSON library version to use.</summary>
+        public decimal JsonLibraryVersion => _settings.JsonLibraryVersion;
+
         /// <summary>Gets a value indicating whether the enum needs another base type to representing an extended value range.</summary>
         public bool HasExtendedValueRange => _schema.Format == JsonFormatStrings.Long;
 

src/NJsonSchema.CodeGeneration.CSharp/Templates/Class.liquid

@@ -62,7 +62,7 @@
 {%- if UseSystemTextJson -%}
     [System.Text.Json.Serialization.JsonPropertyName("{{ property.Name }}")]
 {%-   if property.IsStringEnumArray -%}
-    // TODO(system.text.json): Add string enum item converter
+    // TODO(system.text.json): Add ItemConverterType with enum converter when supported
 {%-   endif -%}
 {%- else -%}
     [Newtonsoft.Json.JsonProperty("{{ property.Name }}", Required = {{ property.JsonPropertyRequiredCode }}{% if property.IsStringEnumArray %}, ItemConverterType = typeof(Newtonsoft.Json.Converters.StringEnumConverter){% endif %})]

src/NJsonSchema.CodeGeneration.CSharp/Templates/Enum.liquid

@@ -13,7 +13,11 @@
 {%- for enum in Enums %}
 {%-   if IsStringEnum -%}
 {%-       if UseSystemTextJson -%}
+{%-           if JsonLibraryVersion >= 9.0 -%}
     [System.Text.Json.Serialization.JsonStringEnumMemberName(@"{{ enum.Value | replace: '"', '""' }}")]
+{%-           else -%}
+    [System.Runtime.Serialization.EnumMember(Value = @"{{ enum.Value | replace: '"', '""' }}")]
+{%-           endif -%}
 {%-       else -%}
     [System.Runtime.Serialization.EnumMember(Value = @"{{ enum.Value | replace: '"', '""' }}")]
 {%-       endif -%}

src/NJsonSchema.CodeGeneration.Tests/EnumGenerationTests.cs

@@ -52,7 +52,7 @@ public async Task When_export_types_is_true_add_export_before_enum_in_typescript
             var schema = NewtonsoftJsonSchemaGenerator.FromType<StringAndIntegerEnumTestClass>(new NewtonsoftJsonSchemaGeneratorSettings());
             var data = schema.ToJson();
 
-            TypeScriptGeneratorSettings typeScriptGeneratorSettings = new TypeScriptGeneratorSettings()
+            TypeScriptGeneratorSettings typeScriptGeneratorSettings = new TypeScriptGeneratorSettings
             {
                 ExportTypes = true
             };
@@ -72,8 +72,8 @@ public async Task When_add_export_keyword_is_false_dont_add_export_before_enum_i
             // Arrange
             var schema = NewtonsoftJsonSchemaGenerator.FromType<StringAndIntegerEnumTestClass>(new NewtonsoftJsonSchemaGeneratorSettings());
             var data = schema.ToJson();
-
-            TypeScriptGeneratorSettings typeScriptGeneratorSettings = new TypeScriptGeneratorSettings()
+            
+            TypeScriptGeneratorSettings typeScriptGeneratorSettings = new TypeScriptGeneratorSettings
             {
                 ExportTypes = false
             };
@@ -144,6 +144,30 @@ public async Task When_enum_has_string_value_then_CS_code_has_EnumMember_attribu
             await VerifyHelper.Verify(code);
             CSharpCompiler.AssertCompile(code);
         }
+
+#if NET9_0_OR_GREATER
+
+        [Fact]
+        public async Task When_enum_has_string_value_then_CS_code_has_JsonStringEnumMemberName_attribute()
+        {
+            // Arrange
+            var schema = NewtonsoftJsonSchemaGenerator.FromType<ClassWithStringEnum>();
+            var schemaData = schema.ToJson();
+
+            // Act
+            var generator = new CSharpGenerator(schema, new CSharpGeneratorSettings
+            {
+                JsonLibraryVersion = 9.0m,
+                JsonLibrary = CSharpJsonLibrary.SystemTextJson
+            });
+            var code = generator.GenerateFile("MyClass");
+
+            // Assert
+            await VerifyHelper.Verify(code);
+            CSharpCompiler.AssertCompile(code);
+        }
+
+#endif
 
         [Fact]
         public async Task When_enum_has_string_value_then_TS_code_has_string_value()

src/NJsonSchema.CodeGeneration.Tests/NJsonSchema.CodeGeneration.Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>net8.0</TargetFrameworks>
+        <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
         <TargetFrameworks Condition="'$(OS)' == 'Windows_NT'">$(TargetFrameworks);net472</TargetFrameworks>
         <IsPackable>false</IsPackable>
         <NoWarn>$(NoWarn),1998,1591,618,IDE1006</NoWarn>

src/NJsonSchema.CodeGeneration.Tests/Snapshots/EnumGenerationTests.When_enum_has_string_value_then_CS_code_has_JsonStringEnumMemberName_attribute.verified.txt

@@ -0,0 +1,32 @@
+//----------------------
+// <auto-generated>
+// </auto-generated>
+//----------------------
+
+
+namespace MyNamespace
+{
+    #pragma warning disable // Disable all warnings
+
+    public enum StringEnum
+    {
+
+        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"0562")]
+        _0562 = 0,
+
+
+        [System.Text.Json.Serialization.JsonStringEnumMemberName(@"0532")]
+        _0532 = 1,
+
+
+    }
+
+    public partial class MyClass
+    {
+
+        [System.Text.Json.Serialization.JsonPropertyName("Bar")]
+        [System.Text.Json.Serialization.JsonConverter(typeof(System.Text.Json.Serialization.JsonStringEnumConverter<StringEnum>))]
+        public StringEnum Bar { get; set; }
+
+    }
+}

src/NJsonSchema.Tests/Generation/SystemTextJson/SystemTextJsonEnumTests.WhenIntegerEnumUseEnumNameAttributes_ThenTheyAreIgnored.verified.txt

@@ -0,0 +1,27 @@
+{
+  "$schema": "http://json-schema.org/draft-04/schema#",
+  "title": "IntegerEnumContainer",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "IntegerCloudCover": {
+      "$ref": "#/definitions/IntegerCloudCover"
+    }
+  },
+  "definitions": {
+    "IntegerCloudCover": {
+      "type": "integer",
+      "description": "",
+      "x-enumNames": [
+        "Clear",
+        "Partial",
+        "Overcast"
+      ],
+      "enum": [
+        0,
+        1,
+        2
+      ]
+    }
+  }
+}

src/NJsonSchema.Tests/Generation/SystemTextJson/SystemTextJsonEnumTests.WhenStringEnumUsesEnumMemberAttribute_ThenItIsUsed.verified.txt

@@ -0,0 +1,27 @@
+{
+  "$schema": "http://json-schema.org/draft-04/schema#",
+  "title": "StringEnumMemberContainer",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "CloudCover": {
+      "$ref": "#/definitions/CloudCoverWithEnumMember"
+    }
+  },
+  "definitions": {
+    "CloudCoverWithEnumMember": {
+      "type": "string",
+      "description": "",
+      "x-enumNames": [
+        "Clear",
+        "Partial",
+        "Overcast"
+      ],
+      "enum": [
+        "Clear",
+        "Partly cloudy",
+        "Overcast"
+      ]
+    }
+  }
+}

src/NJsonSchema.Tests/Generation/SystemTextJson/SystemTextJsonEnumTests.WhenStringEnumUsesJsonStringEnumMemberName_ThenItIsUsed.verified.txt

@@ -0,0 +1,27 @@
+{
+  "$schema": "http://json-schema.org/draft-04/schema#",
+  "title": "StringJsonStringEnumMemberNameContainer",
+  "type": "object",
+  "additionalProperties": false,
+  "properties": {
+    "CloudCover": {
+      "$ref": "#/definitions/CloudCoverWithJsonStringEnumMemberName"
+    }
+  },
+  "definitions": {
+    "CloudCoverWithJsonStringEnumMemberName": {
+      "type": "string",
+      "description": "",
+      "x-enumNames": [
+        "Clear",
+        "Partial",
+        "Overcast"
+      ],
+      "enum": [
+        "Clear",
+        "Partly cloudy",
+        "Overcast"
+      ]
+    }
+  }
+}